Spring Boot電商秒殺實戰 -- 1.基礎環境搭建
阿新 • • 發佈：2018-12-22
記錄學習總結
目標：
1.掌握Spring Boot環境搭建
2.掌握Lombok的整合使用
2.掌握Thymeleaf整合,Result結果封裝
3.掌握Mybatis+Druid整合
4.掌握Jedis整合+通用快取Key封裝
文章總體目錄
Spring Boot專案搭建
Spring Boot環境搭建
這裡使用 IDEA 來進行專案開發，提供了很方便了模板。
整合Lombok
1.選單欄File > Settings > Plugins > Browse repositories
2.搜尋 Lombok Plugin 安裝後，重啟IDEA即可生效
3.新增lombok依賴
<!-- https://mvnrepository.com/artifact/org.projectlombok/lombok --> <dependency> <groupId>org.projectlombok</groupId> <artifactId>lombok</artifactId> <version>1.18.2</version> <optional>true</optional> </dependency>
4.編寫一個實體類 User，使用@Data註解(包含了set和get方法)
@Data
public class User {
private int id;
private String name;
}
其他的Lombok用法這裡不多說，大家可以自行查閱
整合Mybatis+Druid
1.在 pom.xml 新增依賴
<dependency> <groupId>mysql</groupId> <artifactId>mysql-connector-java</artifactId> </dependency> <dependency> <groupId>com.alibaba</groupId> <artifactId>druid</artifactId> <version>1.1.10</version> </dependency>
2.在 application.properties 中新增相關配置
# mybatis
mybatis.type-aliases-package=com.chandler.seckill.domain
mybatis.configuration.map-underscore-to-camel-case=true
mybatis.configuration.default-fetch-size=100
mybatis.configuration.default-statement-timeout=3000
mybatis.mapperLocations = classpath:com/chandler/seckill/dao/*.xml
# druid
spring.datasource.url=jdbc:mysql://localhost:3306/seckill?useUnicode=true&characterEncoding=utf-8&allowMultiQueries=true&useSSL=false
spring.datasource.username=root
spring.datasource.password=root
spring.datasource.driver-class-name=com.mysql.jdbc.Driver
spring.datasource.type=com.alibaba.druid.pool.DruidDataSource
spring.datasource.filters=stat
spring.datasource.maxActive=2
spring.datasource.initialSize=1
spring.datasource.maxWait=60000
spring.datasource.minIdle=1
spring.datasource.timeBetweenEvictionRunsMillis=60000
spring.datasource.minEvictableIdleTimeMillis=300000
spring.datasource.validationQuery=select 'x'
spring.datasource.testWhileIdle=true
spring.datasource.testOnBorrow=false
spring.datasource.testOnReturn=false
spring.datasource.poolPreparedStatements=true
spring.datasource.maxOpenPreparedStatements=20
3.在DAO中新增相關注解
@Mapper
public interface UserDao {
@Select("select * from user where id = #{id}")
public User getById(@Param("id")int id);
@Insert("insert into user(id,name) values(#{id},#{name})")
public int insert(User user);
}
整合Thymeleaf
1.在 pom.xml 新增依賴
<dependency>
<groupId>org.springframework.boot</groupId>
<artifactId>spring-boot-starter-thymeleaf</artifactId>
</dependency>
2.在 application.properties 中新增相關配置
# thymeleaf
spring.thymeleaf.prefix=classpath:/templates/
spring.thymeleaf.suffix=.html
spring.thymeleaf.cache=false
spring.thymeleaf.servlet.content-type=text/html
spring.thymeleaf.enabled=true
spring.thymeleaf.encoding=UTF-8
spring.thymeleaf.mode=HTML5
整合Jedis
1.在 pom.xml 新增依賴
<dependency>
<groupId>redis.clients</groupId>
<artifactId>jedis</artifactId>
</dependency>
2.在 application.properties 中新增相關配置
#redis
redis.host=192.168.25.128
redis.port=6379
redis.timeout=3
redis.password=123456
redis.poolMaxTotal=10
redis.poolMaxIdle=10
redis.poolMaxWait=3
Result結果封裝
很多時候都是需要返回JSON物件，根據需求事先先封裝好一個結果物件，方便複用。
因為希望的返回結果形式為：
{
code:0,
msg:success,
name:chandler
}
所有最終設計的Result結果類為：
@Data
public class Result<T> {
private int code;
private String msg;
private T data;
/**
* 成功時的呼叫
* @param data
* @param <T>
* @return
*/
public static <T> Result<T> success(T data){
return new Result<T>(data);
}
/**
* 失敗時候的呼叫
* @param cm
* @param <T>
* @return
*/
public static <T> Result<T> error(CodeMsg cm){
return new Result<T>(cm);
}
public Result(T data) {
this.code = 0;
this.msg = "success";
this.data = data;
}
public Result(CodeMsg cm) {
if (cm == null) {
return;
}
this.code = cm.getCode();
this.msg = cm.getMsg();
}
}
@Data
@AllArgsConstructor
public class CodeMsg {
private int code;
private String msg;
//通用異常
public static CodeMsg SUCCESS = new CodeMsg(0,"success");
public static CodeMsg SERVER_ERROR = new CodeMsg(500100,"服務端異常");
//TODO其他異常
}
通用快取Key封裝
我們還需要建立一個 Redis 服務方便進行快取操作
先定義一個讀取application.properties檔案中 redis 配置的類
@Component
@Data
@ConfigurationProperties(prefix = "redis")
public class RedisConfig {
private String host;
private int port;
private int timeout;//秒
private String password;
private int poolMaxTotal;
private int poolMaxIdle;
private int poolMaxWait;//秒
}
有了配置檔案中的資訊我們在來建立一個工廠類，方便初始化 redis 連線池
@Service
public class RedisPoolFactory {
@Autowired
RedisConfig redisConfig;
//註冊bean物件
@Bean
public JedisPool jedisPoolFactory(){
JedisPoolConfig jedisPoolConfig = new JedisPoolConfig();
jedisPoolConfig.setMaxIdle(redisConfig.getPoolMaxIdle());
jedisPoolConfig.setMaxTotal(redisConfig.getPoolMaxTotal());
jedisPoolConfig.setMaxWaitMillis(redisConfig.getPoolMaxWait());
JedisPool jp = new JedisPool(jedisPoolConfig,redisConfig.getHost(),redisConfig.getPort(),redisConfig.getTimeout() * 1000,redisConfig.getPassword(),0);
return jp;
}
}
為了方便我們在讀取 key 值的時候能夠顯示的讀取相關值且存入的key值 在不同模組間不同名重複和後期拓展，我們這裡稍微對讀取和儲存 key 值進行一點加工設計,實現了 KeyPrefix 介面和 BasePrefix 基礎抽象類，這樣其他模組的新增只需要繼承基礎抽象類即可。
- 介面擴充套件類
public interface KeyPrefix {
public int expireSeconds();
public String getPrefix();
}
- 基礎抽象類
@AllArgsConstructor
public abstract class BasePrefix implements KeyPrefix{
private int expireSeconds;
private String prefix;
public BasePrefix(String prefix) {
//0代表永不過期
this(0,prefix);
}
@Override
public int expireSeconds(){
return expireSeconds;
}
@Override
public String getPrefix() {
String className = getClass().getSimpleName();
return className+":"+prefix;
}
}
- 業務相關類
public class OrderKey extends BasePrefix {
public OrderKey(int expireSeconds, String prefix) {
super(expireSeconds, prefix);
}
}
public class UserKey extends BasePrefix {
public UserKey(String prefix) {
super(prefix);
}
public static UserKey getById = new UserKey("id");
public static UserKey getByName = new UserKey("name");
}
- 最後是比較關鍵的RedisService 服務類,快取相關操作都封裝在這個類中
@Service
public class RedisService {
@Autowired
JedisPool jedisPool;
/**
* 獲取單個物件
*
* @param prefix
* @param key
* @param clazz
* @param <T>
* @return
*/
public <T> T get(KeyPrefix prefix, String key, Class<T> clazz) {
Jedis jedis = null;
try {
jedis = jedisPool.getResource();
String realKey = prefix.getPrefix() + key;
String str = jedis.get(realKey);
T t = stringToBean(str, clazz);
return t;
} finally {
returnToPool(jedis);
}
}
/**
* 設定物件
* @param prefix
* @param key
* @param value
* @param <T>
* @return
*/
public <T> boolean set(KeyPrefix prefix,String key,T value){
Jedis jedis = null;
try {
jedis = jedisPool.getResource();
String str = beanToString(value);
if (str == null || str.length() <= 0) {
return false;
}
String realKey = prefix.getPrefix() + key;
int seconds = prefix.expireSeconds();
if (seconds <= 0){
jedis.set(realKey,str);
} else {
jedis.setex(realKey,seconds,str);
}
return true;
} finally {
returnToPool(jedis);
}
}
/**
* 判斷 key 是否存在
* @param prefix
* @param key
* @param <T>
* @return
*/
public <T> boolean exists(KeyPrefix prefix,String key){
Jedis jedis = null;
try {
jedis = jedisPool.getResource();
String realKey = prefix.getPrefix() + key;
return jedis.exists(realKey);
} finally {
returnToPool(jedis);
}
}
/**
* 執行原子增加 key 值
* @param prefix
* @param key
* @param <T>
* @return
*/
public <T> Long incr(KeyPrefix prefix,String key){
Jedis jedis = null;
try {
jedis = jedisPool.getResource();
String realKey = prefix.getPrefix() + key;
return jedis.incr(realKey);
} finally {
returnToPool(jedis);
}
}
/**
* 減少 key 值
* @param prefix
* @param key
* @param <T>
* @return
*/
public <T> Long decr(KeyPrefix prefix,String key){
Jedis jedis = null;
try {
jedis = jedisPool.getResource();
String realKey = prefix.getPrefix() + key;
return jedis.decr(realKey);
} finally {
returnToPool(jedis);
}
}
private <T> String beanToString(T value) {
if (value == null) {
return null;
}
Class<?> clazz = value.getClass();
if (clazz == int.class || clazz == Integer.class){
return ""+value;
} else if (clazz == Long.class || clazz == long.class){
return "" + value;
} else if (clazz == String.class){
return (String) value;
} else {
return JSON.toJSONString(value);
}
}
private <T> T stringToBean(String str, Class<T> clazz) {
if (str == null || str.length() <= 0 || clazz == null) {
return null;
}
if (clazz == int.class || clazz == Integer.class) {
return (T) Integer.valueOf(str);
} else if (clazz == String.class) {
return (T) str;
} else if (clazz == Long.class || clazz == long.class) {
return (T) Long.valueOf(str);
} else {
return JSON.toJavaObject(JSON.parseObject(str), clazz);
}
}
private void returnToPool(Jedis jedis) {
if (jedis != null) {
jedis.close();
}
}
}
測試驗證
環境都搭建配置之後測試是必不可少的環節，開始動手搞起來。
1.建立測試 TestController 類
@Controller
@RequestMapping("/test")
public class TestController {
@Autowired
UserService userService;
@Autowired
RedisService redisService;
@RequestMapping("/hello")
@ResponseBody
public Result<String> home(){
return Result.success("Hello world");
}
@RequestMapping("/error")
@ResponseBody
public Result<String> error(){
return Result.error(CodeMsg.SERVER_ERROR);
}
@RequestMapping("/hello/themaleaf")
public String themaleaf(Model model){
model.addAttribute("name","Chandler");
return "hello";
}
@RequestMapping("/db/get")
@ResponseBody
public Result<User> dbGet(){
User user = userService.getById(1);
return Result.success(user);
}
@RequestMapping("/redis/get")
@ResponseBody
public Result<User> redisGet(){
User user = redisService.get(UserKey.getById,""+1,User.class);
return Result.success(user);
}
@RequestMapping("/redis/set")
@ResponseBody
public Result<Boolean> redisSet(){
User user =new User();
user.setId(1);
user.setName("Chandler");
redisService.set(UserKey.getById,""+1,user);
return Result.success(true);
}
}
2.測試Result類是否能夠返回我們需要的json格式
3.測試Themaleaf是否配置成功
4.測試User類是否正常
5.測試Redis配置是否成功
進入 Redis 中檢視
這樣大概的環境流程驗證OK，接下來就可以開始實現功能開發了~~